Making the decision on which treatment to use is a stepwise process. It really begins with the suspicion of cancer aroused by signs or symptoms, then proceeds through the diagnostic process outlined in How Cancer is Diagnosed. Once the diagnosis is confirmed by a positive biopsy , several factors have to be considered.
The Stage How far along the tumor is in its development is the most critical factor. Sometimes the stage isn't known until a surgeon actually has a look at the tumor. But there are other ways to find out what stage the malignancy has reached.
During the staging process many parts of the body will be searched for evidence of cancer. Tests will discover the extent of the spread and the involvement with other tissues at the primary site. This will involve blood tests to see how organs such as the kidneys and liver are functioning. Imaging techniques such as chest x-rays and CT scans will be used to see if there is any involvement of the lungs either directly or by spread.
Other specialized tests will be ordered according to the primary site and the type of tumor being investigated. Each type of cancer has a typical pattern of spread, so different specific areas of the body will be investigated in each case.
Prostate cancer, for example, usually spreads to bone, so bone scans, bone x-rays and blood tests will be quite important. Lung cancers can spread to the center of the chest (mediastinum), an area that can be mapped with a CT scan and looked at directly through a scope (mediastinoscopy). Cancers of the stomach and bowel commonly spread to the liver, so liver scans and blood tests will be needed to be sure about those areas.
